I have discovered that, when making a yard with regular tubular or FasTrack full curves, the tracks are spaced out so far, that you probably could fit another track in between them! How do you make a realistic FasTrack yard that can acommodate trains that go through O42 curves?
using tubular track, one trick is that on an O-72 switch, instead of using an O72 curve coming off, use a half section of O31. It has the same # of degrees to bring teh track back parallel to the feed, but it allows for much closer placement.
I’ve read about this problem before with fastrack - dunno. Can your trains approach your yard from either end? If so, maybe you could have “two” overlapping yards with the “parking” tracks staggered between each other… You could have a bypass track at the “front” end of your yard to access the “2nd yard”, I guess.
Another alternative is to cut off equal portions of the switch curved section, a curved track section, and rejoin them permanently using plastic strips glued under the roadbed as strongbacks. This requires some precision mitre cuts and soldering but it can be done.
For closely-spaced yard tracks, check this out:
http://www.trains.com/community/forum/topic.asp?TOPIC_ID=59523